An agent skill is a small, focused capability that an AI agent can load when a task calls for it. It usually lives in a folder centered on a SKILL.md file, with optional scripts, references, and assets beside it.
The useful idea is not “give the agent more instructions.” It is “make a good way of doing one kind of work available at the right moment.”
A skill has a job
Strong skills have a clear trigger and a clear finish line. A skill for browser QA should explain when it applies, what it checks, how it records findings, and what a completed review looks like. A vague file full of general advice is harder for both people and agents to trust.
What belongs in SKILL.md
- Purpose: the task the skill is meant to handle.
- Triggers: the words, file types, or situations that make it relevant.
- Workflow: concrete steps, decision points, and useful defaults.
- Constraints: what the agent must not do without approval.
- Verification: how to check the result instead of declaring success too early.
Provenance is part of the skill
Before installing a skill, inspect its repository, publisher, license, update history, scripts, and requested access. Treat the file as untrusted text until you understand what it asks an agent to do. A skill can be helpful and still be a poor fit for a sensitive environment.
Start with one repeatable task
Pick a workflow you perform often: writing release notes, testing a web page, researching a company, or preparing a pull request. Browse the EveryAI skills library, compare a few sources, and try one in a constrained workspace. The goal is a more dependable result, not a larger folder of unused instructions.